Journal name: Neuropsychiatric Disease and Treatment Article Designation: ORIGINAL RESEARCH Year: 2018 Volume: 14 Neuropsychiatric Disease and Treatment Dovepress Running head verso: Steffenburg et al Running head recto: Are ASDs comorbid in SM open access to scientific and medical research DOI: 154966 Open Access Full Text Article ORIGINAL RESEARCH Children with autism spectrum disorders and selective mutism Hanna Steffenburg Background: It has been suggested that autism spectrum disorder (ASD) might be a “comorbid” Suzanne Steffenburg condition in selective mutism (SM). Christopher Gillberg Methods: In this retrospective study, we examined medical records of children with SM Eva Billstedt diagnosis (n=97) at a medical center specializing in assessment of ASD. Results: Mean age for onset of SM symptoms was 4.5 years and mean age at SM diagnosis Gillberg Neuropsychiatry Centre, Institute of Neuroscience was 8.8 years. SM was more common among girls (boy:girl ratio=2.7:1). We found that 63% and Physiology, University of the study group had an ASD (no gender difference). The SM group with combined ASD had of Gothenburg, Sahlgrenska later onset of symptoms, higher age at diagnosis, more often a history of speech delay, and a Academy, Gothenburg, Sweden higher proportion of borderline IQ or intellectual disability. Conclusion: The results highlight the risk of overlap between ASD and SM. Keywords: selective mutism, autism spectrum disorders, Asperger syndrome, autistic disorder For personal use only. Introduction Selective mutism (SM) is described in the Diagnostic and Statistical Manual of Mental Disorders, Fourth edition (DSM-IV) and Fifth edition (DSM-5) as a rare anxiety disor- der, characterized by a consistent failure to speak in specific social situations in which there is an expectation of speaking, despite speaking in other situations1,2 (Americal Psychological Association 1994; 2013). In 1877, Kussmaul described SM and he used the term aphasia voluntaria to underline the awareness and the free will not to speak.3 In 1934, Tramer3 introduced the concept of elective mutism that continued emphasiz- ing the voluntariness in not speaking in certain situations. Throughout its history, SM has been described as an oppositional trait with an unwillingness to speak rather than a single diagnosis.3 In the publication of DSM-IV,1 the diagnosis of SM was included, Neuropsychiatric Disease and Treatment downloaded from https://www.dovepress.com/ by 54.70.40.11 on 21-Dec-2018 which underlines the lack of speech in certain situations. The shift broadened the diag- nosis phenomenology, from a voluntarily controlled and defiant behavior to a pattern of reaction in response to an overwhelming or threatening context change.4 The failure to speak cannot be explained by lack of language skills. The duration of disturbance should be at least 1 month. The disorder should not be categorized as a communication disorder, pervasive developmental disorder (PDD), schizophrenia, or other psychotic disorder.1,2 In the DSM-5, SM is categorized under the category of Anxiety Disorders, and this marks an increased focus on supposed underlying social anxiety problems. Correspondence: Eva Billstedt Communication patterns in SM vary from total absence of speech in almost all Gillberg Neuropsychiatry Centre, situations to lack of speech in only certain situations. The most common situations University of Gothenburg, Kungsgatan 12, Gothenburg 411 19, Sweden for the appearance of SM symptoms are in school, where the teacher is the person Tel +46 31 342 5980 that the child is least likely to talk to.5 Sometimes the child can talk to select students, Fax +46 31 342 5979 Email [email protected] sometimes to nobody at all. Commonly, the child speaks normally at home with the submit your manuscript | www.dovepress.com Neuropsychiatric Disease and Treatment 2018:14 1163–1169 1163 Dovepress © 2018 Steffenburg et al. This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution – Non Commercial (unported, v3.0) License (http://creativecommons.org/licenses/by-nc/3.0/). By accessing the work you http://dx.doi.org/10.2147/NDT.S154966 hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms (https://www.dovepress.com/terms.php). Powered by TCPDF (www.tcpdf.org) 1 / 1 Steffenburg et al Dovepress family, but the opposite situation, where the child speaks at Participants and methods school but not at home, has also been described.6 Procedure Onset of SM symptoms is reported to be 2.7–4.1 years.4 All individuals at the Child Neuropsychiatry Clinic (CNC) Usually, the symptoms are not noticed until the child starts in Gothenburg who had received a DSM-IV diagnosis of SM primary school, which might be explained by the increased between 2003 and 2014 were eligible for participation in the social demand and increased demands for performance, study. CNC is a regional clinic in Gothenburg, West Sweden, making the symptoms more obvious.3 The long interval focusing on the assessment of neurodevelopmental disorders between symptom onset and detection of problems is prob- (autism, ADHD, Tourette syndrome, etc), and at that period ably explained by the fact that children often speak without also on the assessment of SM, in children and adolescents. any problem in the home environment. All data were retrieved from medical records including the The reported prevalence rates vary between 0.2% and diagnosis, except for in some cases where there was an ASD 0.8%.4,7–9 SM is reported to be more common among girls diagnostic re-evaluation based on the medical records at the than boys, with an estimated girl:boy ratio varying between time of the study, by the second author SZ, who was the 2.6:1 and 1.5:1.3 SM is described as a condition in children clinical doctor for a large proportion of the study group. The but can also be recognized in adults; however, the symptoms time period was chosen to coincide with the introduction of are more often categorized as social phobia,3 under the a computerized medical record system at the CNC in 2003, anxiety disorders umbrella. A few longitudinal studies of making data retrieval easier. SM have been performed and the persistence of symptoms varies in the literature, from months to several years. There Participants is usually remaining shyness; social anxiety;3 and lack of One hundred and six individuals were diagnosed as having self-confidence, independence, achievement, and social com- SM during the selected time period at the CNC. Nine indi- munication abilities into teenage and adult life.6,10 viduals (4 girls and 5 boys) were excluded because there was In addition to anxiety, other associated symptoms/comor- some uncertainty about diagnosis or because the medical For personal use only. bidities have also been reported, such as speech and language records contained too scanty information, leaving a total of problems,11,12 obsessive compulsive disorder,13 Fragile X 97 individuals (71 girls and 26 boys) who were included in syndrome,6 attention deficit hyperactivity disorder (ADHD),4 the study. The age at assessment in the CNC ranged from depression, panic disorder, disassociate disorders, and other 4 to 18 years (median=8 years). somatic complaints.3 Kristensen reported an association between SM and developmental disorders relating to commu- The clinical/diagnostic assessment nication, learning, motor skills in a study of 54 children with The clinical/diagnostic assessments had been performed by a SM. She found that 7% of the participants also fulfilled the team that included a medical doctor/child psychiatrist and a criteria for Asperger syndrome (AS), and an additional 7% met clinical psychologist at CNC, both with extensive experience the criteria for mild intellectual disability (ID).12 Anderson and in the field of SM and ASD, including diagnostic work-up. The Thomsen14 found in a group of 37 children with SM that 4 of diagnoses were based on all the available information provided Neuropsychiatric Disease and Treatment downloaded from https://www.dovepress.com/ by 54.70.40.11 on 21-Dec-2018 them had AS. Furthermore, autism spectrum disorder (ASD) by the files, the clinical interview, and the clinical impression has been found to occur more frequently in SM families.14 according to the LEAD-principle (Longitudinal, Expert, All, The purpose of the present study was to examine the Data).16 All individuals were examined individually, and at prevalence of ASD in a relatively large clinical sample of least 1 parent was interviewed. The interview always cov- children with SM who were referred to a center specializing ered language development, onset of SM symptoms, age at in the assessment of neurodevelopmental disorders. Further- diagnosis, and whether or not the child had been exposed to more, a study on joint attention, a specific aspect of social a non-Swedish language environment at home. The clinical communication, reported fewer episodes of joint attention assessment procedure included instruments regularly used in in the SM group than in comparison group.15 More girls clinical practice, such as DSM-IV checklists, parent/teacher than boys are affected by SM;3 however, if that is the case in questionnaires